Method of coating fabrics with cellulose derivatives



Sept. 22, 1931. G. SCHNEIDER METHOD OF COATING FABRICS WITH CELLULOSE DERIVATIVES Filed May 21, 1926 OR SOLUTION OFA DERIVATIVE OF CELLULOSE- FILM CONTAINING DERIVATIVE 0F CELLULOSE POLISHED SURFACE FABRIC WETTED WITH SOLVENT FOR 5OLUTION OF A DERIVATIVE OF CELLULOSE SOLVENT FOR OR SOLUTION OF A DERIVATIVE OF CELLULOSE 6 a H E Tn N E m R E O EVS T m me H m .9 5w m o e w G B F mo H Patented Sept. 22, 1931 UNITED STATES PATENT OFFICE GEORGE SCHNEIDER, OF CUMBERLAND, MARYLAND, ASSIGNOR '10 CELANESE CORPO- RATION OF AMERICA, A CORPORATION 01 DELAWARE METHOD OF COATING FABRICS WITH CELLULOSE DERIVATIVES Application filed Kay 21, 1928- Serial No. 110,828.

The invention consists in a method of obtaining a-highly polished water-proof surface of a cellulose ester or ether which is firmly attached to one side of a fabric.

5 Processes are known wherein the fabric to be treated is painted, sprayed or otherwise treated with cellulose ester or ether solutions, for instance, cellulose acetate solution. In these processes the fabric becomes more or less impregnated with the solution and when dried attains a stiffness which is not only undesirable but precludes its use in numerous applications such as, for instance, book binding, millinery, shoe covering, etc.

Further, in the processes above mentioned, many coatings, sprayings, etc. are necessary before the desired high finish is obtained, due to the absorption of the solution by the fabric, the resulting fabric having excessive weight besides being extravagant in the use of the cellulosic solution,

In carrying out the present invention, a properly prepared solution of a cellulose ester or ether, in particular cellulose acetate, with or without softening agents or plastifiers in suflicient quantity to obtain the desired suppleness in the completed fabric is spread by means of a knife edge or doctor blade to the desired thickness on a highly polished surface. This solution may or may not contain dye-stuffs, pigments, filling materials or effect materials as desired. The film thus produced is allowed to dry either at normal temperatures or at elevated temperatures. When the film is dry any desired fabric is firmly attached to the surface of the film by moistening the fabric with a solvent for the film and then firmly pressing the moistened fabric against the film. The solvent acts as an adhesive between the fabric and the film. The adhesion of the fabric to the film can also be accomplished by first wetting the fabric with a dilute solution of the cellulose ester or ether and then firmly pressing the wetted fabric against the film. The combined fabric and film are then redried to remove the solvent used to wet the fabric and the product is then stripped as a whole from the highly polished surface.

By my invention the surfaced fabric so obtained is easily regulated as to weight by the thickness of fihn applied to the polished surface. The product retains a suppleness not possible by any other known method and a polished surface is obtained with great economy of solution.

My invention may be carried out intermittently by using sections of glass or metal for the polished surface or it may be carried out continuously by employing a highly polished, slowly revolving metal drum or wheel. t

For visual illustration of some modes of carrying out this invention, reference is had to the accompanying drawings wherein Figure 1 shows diagrammatically one mode of carrying out this invention Flgure 2 shows another mode of carrying out the invention, and

Figure 3 shows a diagrammatic cross sect1on of the coated fabric made by this invention.

Referring to Figure 1, a film 1 containing a derivative of cellulose is cast on a smooth or polished surface 2 which surface may be of glass or metal. Thereupon a piece of fabric 3 which is wetted with a solvent for or a solution of the derivative of cellulose contained in the film 1 is superposed upon the film l and pressed thereon. After the solvent has evaporated, the fabric with the attached film is stripped from the polished surface 2.

Referring to Figure 2 a solution containing the derivative of cellulose is cast from the hopper 4 onto the highly olished slowly revolving metal drum or w eel 5 to form the film l. The fabric 3 is rolled from the roll 6 under a bath of a solvent for or a solution of a derivative of cellulose contained in the vessel 7 and is then pressed against the fihn 1 by means of the spring pressed roll 8. The assembly of fabric and fihn is then passed between rolls in the dryer 9 and the finished material is wound on the roll 10,

The following examples will serve to illustrate the process:

Ewample 1.A 6% to 20% solution of The glass and fihn are then warmed at about C. until the solvents are entirely volatilized. The fabric which is to be surfaced is then well wet with acetone or other volatile solvent of the cellulose acetate and gently but firmly pressed on the film. The

slate is a ain warmed for a few minutes to ry the abric and the fabric with the attached film is then stripped from the lass.

E'zmmple 2.-A 6% to 20% solution 0 cellulose butyrate, according to the thickness of film desired, in a mixture of ethyl alcohol and benzol or any other solvent or solvents containing from 40% to 90% (based on the cellulose butyrate) softeners or plastifiers according to the suppleness desired in the finished product, is spread on highl polished glass late to the desired thickness. The lass an film are then warmed at about 40 until the solvents are entirely volatilized. The fabric which is to be surfaced is then well wet with a dilute volatile solution of the cellulose butyrate and the fabric is then gently but firmly resesd on the film. The plate is again warme for a few minutes to dry the fabric and the fabric with the attached film of cellulose butyrate is then shipped from the glass. wample 3.-A 6% to 20% solution of cellulose nitrate, according to the thickness of 40 film desired, is made by dissolving the nitrate of cellulose in a mixture of butyl alcohol, butyl acetate or in any other solvent or mixture of solvents. To this solution is added from 25 to 90% (based on the cellulose nitrate) of softeners or plastifiers ac- 'cordin to the suppleness desired in the finishe roduct. This solution, containin the plasti ers, is then spread on a bi hly ished glass plate or other olishe sur ace to the desired thickness. his film is then treated as described in Examples 1 and 2 except that the fabric is wetted with a solvent or solvents of the nitrocellulose.

Example 4.A 5% to 25% solution of ethyl cellulose, depending upon the thick ness of film desired, is prepared by dissolving the same in benzol or any other suitable organic solvent for the ethyl cellulose and to this solution is added 40 to 90% (basis of the ethyl cellulose) of softeners or lastifiers, depending upon the suppleness desired in the finished product. This solution, with the softeners or plasticizers mixed therewith is then spread on a highly polished surface to any desired thickness. This film is then dried as in the previous examples and any desired fabric is then attached thereto by wetting the fabric with an suitable volatile solvent for the ethyl ce lulose and ressing the same on to the film as descnbed in the other exam les. The combined film and fabric is t en warmed to remove the solvent after which the com-' I have found that a multitude of very valuable effects can be obtained by employing, either intermittently on glass sections or on metal plates or continuously on metallic drums or wheels, matted or suitably atterned surfaces. Also by incorporating yestuffs, i ments or materials for effect with the ce u osic solution, I can obtain a wide variation of products of great value in the arts. These variations and modifications are all to be considered within the scope of my invention.

The coated fabrics obtained by the processes outlined above can be utilized in a great many of the industrial arts. A few examples of the uses to which they may be put are the following: Imitation metallized fabric, glazed cloth, shoe coverings for millinery, bookbinding, etc. The Ego ucts resulting from this process are to considered as within the scope of my invention.

When I use the term plastifier in the claims I include gelatinizers such as mono oil, triphenyl phosphate, diethylphthalate, etc. or any other suitable gelatinizer, swellin agent or high boiling point solvent of the ce lulose derivative. Also the term fabric as used in the claims is to be construed as includin fabrics of silk, cotton, wool or any! other abric made fromnatural or artificial fibre or mixtures thereof as well as paper (transparent or otherwise}, prepared leather or other-artificial or natural tlssues or textures.

Having described my invention what I dey atent leather, 9

thus wetted fabric against the film, thereby attaching the fabric to the film, and then removing the fabric, with the film attached thereto, from the supporting surface.

2. A process of producing a supple surface or coating of plastified cellulose acetate on a fabric backing which comprises a coating a solution of said cellulose acetate on a highly polished rigid surface, evaporating the solvent and drying the film thus formed at an appropriate temperature, wetting a fabric with a dilute solution of cellulose acetate and pressing the thus wetted fabric against the film, thereby attaching the fabric to the film, drying the combined fabric and film to remove the solvent and then removing the fabric, with the film attached thereto, from the highly polished surface.

3. A process of producing a supple surface or coating of plastified cellulose nitrate on a fabric backing which comprises coating a solution of said cellulose nitrate on a highly polished rigid surface, evaporating the solvent and drying the film thus formed at an appropriate temperature, wetting a fabric with a dilute solution of cellulose nitrate and pressing the thus wetted fabric against the film, thereby attaching the fabric to the film, drying the combined fabric and film to remove the solvent and then removing the fabric, with the film attached thereto, from the highly polished surface.

4:. A process of producing a supple surface or coating of plastified ethyl cellulose on a fabric backing which comprises coating a solution of said ethyl cellulose on a highly polished rigid surface, evaporating the solvent and drying the film thus formed at an appropriate temperature, Wetting a fabric with a dilute solution of ethyl cellulose and pressing the thus wetted fabric against the film, thereby attaching the fabric to the film, drying the combined fabric and film to remove the solvent and then removing the fabric, with the film attached thereto, from the highly polished surface.

In testimony whereof, I have hereunto subscribed my name.

GEORGE SCHNEIDER. 

